Bio Test 4

The diagram shows the structure of adenosine diphosphate (ADP)

What describes the process of conversion of ADP to ATP?

• an input of energy as both phosphate groups separate from ribose

• a release of energy as one phosphate group detaches

• a release of energy as a third phosphate group is attached

• an input of energy as a third phosphate group is attached

William is listing the changes to matter and energy that occur during the process of photosynthesis. Which of these examples should he include in his list?

• nuclear changes that convert hydrogen and oxygen into carbon

• chemical changes that convert carbohydrates into smaller molecules

• changes that convert light energy into chemical energy stored in carbohydrates like sugar

• changes that convert chemical energy into heat and light

Taylor is explaining why chlorophyll is classified as a plant pigment and how it is useful in photosynthesis. Which property of chlorophyll would be most appropriate for her to cite?

• chlorophyll's ability to absorb red and blue light?

• chlorophyll's absorption of green color

• chlorophyll's presence in the stroma

• chlorophyll's reactivity with oxygen

Mimi is asked to describe the structures of chloroplast. She writes the following sentence: "A chloroplast contains thylakoid stacks, called stroma, that are surrounded by fluid-filled grana."

Which change to the sentence is necessary to make the sentence accurate?

• Replace "grana" with "chlorophyll"

• Replace "stroma" with "chlorophyll"

• Switch the terms "stroma" and "grana"

• Switch the terms "thylakoid" and "stroma"

Xavier is describing the role of energy carriers, such as NADP+, in photosynthesis. Which property of NADP+ should Xavier cite?

• the chemical bonds formed by electrons in its molecular structure to carry phosphates

• its ability to accept and release two high-energy electrons

• its reactivity with oxygen, water, and carbon dioxide

• its ability to emit a stream of electrons in a nuclear reaction

The overall chemical equation that describes photosynthesis is shown below.

6CO2 + 6H2O ---> (sunlight) C6H12O6 + 6O2

By analyzing this equation, which property of photosynthesis can be identified?

• the chemical changes that occur only during the light-dependent reactions

• the chemical changes that occur only during the light-dependent reactions

• the source of carbon atoms in the carbohydrate product (sugar)

• the formulas and roles of electron carriers

During photosynthesis, what best describes the role of the compound with the chemical formula C6H12O6

• a product that is not useful because of its low-energy chemical bonds

• a product that is useful because of its high-energy chemical bonds

• a reactant that is useful because of its high-energy chemical bonds

• either a product or a reactant, depending on whether the cell needs to store energy or release energy

What BEST describes the roles of photosystem I and photosystem II in the process of photosynthesis?

• They form ATP as hydrogen ions cross the thylakoid membrane

• They absorb sunlight and distribute the energy as heat

• They transfer electrons from a series of intermediates to form NADPH

• They absorb sunlight and transfer the energy to electrons

Which is the role of the electron transport chain in the process of photosynthesis?

• cycling electrons from photosystem I to photosystem II

• adding energy to the electrons that enter photosystem I

• carrying electrons from photosystem II to photosystem I, pulling in H+ ions

• removing electrons from the chloroplast

During the light-dependent reactions of photosynthesis, which event must occur for ATP synthase to function properly?

• Hydrogen ions must pass through a channel within ATP synthase

• molecular oxygen must combine with ATP synthase

• a molecule of ATP must release a phosphate group to become ADP

• Photosystem I and photosystem II must be deactivated